GPIB SCPI Communication with Agilent E3631A - Invalid separator error

[Micha1177]

Hello,

I'm using a NI PXI-8106 Controller including a GPIB-Connector to communicate with a Agilent E3631A power supply. Therefor I downloaded the most recent Agilent Device Driver I obtained through the LabView "Getting Started"-Screen-Option "Tools->Instrumentation->Find Instrument Driver".

For testing I made a simple VI, initialising GPIB communication (GPIB0::05::INSTR), setting output 1 to 1V, enabling output and closing the communication port using the Agilent VI's. This always resulted in error -103 at the power supply, meaning "invalid separator", which first occures when the "*IDN?"-SCPI-Command is sent in the Initialize-VI from Agilent.

No problem at all occured while communicating with the power supply via RS-232, using the same VIs. (Which, apparently, isn't what i want to do ;))

I tried to pinpoint the problem by rebuilding the Agilent-VI using LabViews VISA-VI's. It seems like the "*IDN?"-String (and any other SCPI-Command) is sent in some "faulty" way by the LabView VISA Write-VI when using GPIB.

NI-Spy-Protocol using GPIB:

    Description                                                    Status

 1  viParseRsrc(0x029F0C58, "GPIB0::5::INSTR", 1, 0)               0

 2  VISA Open ("GPIB0::5::INSTR", False, 0, 0, "GPIB0::5::INSTR")  0

 3  VISA Set Attribute ("GPIB0::5::INSTR", TMO_VALUE, 10000)       0

 4  VISA Get Attribute ("GPIB0::5::INSTR", INTF_TYPE, 1)           0

 5  VISA Clear ("GPIB0::5::INSTR")                                 0

 6  VISA Write ("GPIB0::5::INSTR", "*IDN?")                        0

 7  VISA Read ("GPIB0::5::INSTR", 256)                             0xBFFF0015

Agilent GPIB (IEEE-488)-Settings: Adress 5 (it is only possible to change the GPIB Adress, everything else is fix)

PXI GPIB-Settings:
GPIB Interface ID: GPIB0

Primary Adress: 0

Secondary Adress: none

System controller: True

I/O Timeout: 13 (10sec)

Autopolling: True

Send EOI at End of Write: True

Terminate Read on EOS: False

EOS Byte: 0

8-bit EOS Compare: False

SET EOI with EOS on Write: False

I also implemented a wait-cycle of 100ms between each step (VISA Open, VISA clear, VISA write, VISA read) as it was mentioned as a possible solution to a GPIB communications problem elsewhere in this forum, but that also didn't help.

Anyone got an idea how to fix this?

Many thanks in advance,

Michael

[Micha1177]

How embarassing... problem resolved

Someone from another department was kind enough to borrow me his E3631A Power Supply aaand - it's a miracle - it works.

Seems like the last repair at Agilent fixed the defective adjust-knob, but had some effect to the GPIB interface...

Well... easy fix... at last

[VINAY KUMAR D.I]

dear Micheal,

as u told u r using 8106 controller for communicating with agilent power supply.

can you please let me know what type of GPIB cable u used.

is there is any NI part number for that?

usually normal GPIB cables will be bulk head connector. in 8106 it's a small connector.was there is any adaptor attached to the controller?

you can mail me the info, if you have any to my id.

thanks in advance.

Regards,

[Dennis_Knutson]

When asking a new question, it is recomended that you start a new thread and not post to an older, unrelated one.

All you have to do is do a search for PXI-8106 and you will find the product page at https://www.ni.com/en-us/support/model.pxi-8106.html.

Look under the accessories for cables.

[VINAY KUMAR D.I]

thanks for the info.

i found the accessory.